package 二叉树相关问题;

public class 合并二叉树 {

    public TreeNode mergeTrees(TreeNode root1, TreeNode root2) {
          if (root1==null)
              return root2;
          if (root2==null)
              return root1;
        TreeNode root = new TreeNode(root1.val + root2.val);
        root.right=mergeTrees(root1.right, root2.right);
        root.left=mergeTrees(root1.left,root2.left);
        return root;
    }
}
